HP Tuners Section B Disable the Evaporative Emission System (EVAP) Codes
Having disabled the Secondary O2 Sensor codes in Section A we move on to the EVAP codes. We are doing a batch of codes at a time in this tutorial, but once you get through it once, you are welcome to disable all the necessary codes on your second LS Swap project all at once ha ha.
It's worth repeating there are two schools of thought when it comes to LS Swaps and disabling the codes, some say drive the truck and see what codes it throws than research them a bit and if applicable, delete them. Nothing wrong with that method, but since I like to prep my PCM ahead of time before the engine even swallows a drop of gasoline, and especially since I know exactly what was deleted after all I deleted it, we might as well prevent those Codes from popping up ahead of time. Also and this may tip the scales, if you do your diligence and disable all the codes the best you can for the components you deleted than your MIL should not come on. However if it does, you should turn off the engine and look up the code rather than ignoring it assuming, eh it's probably for one of the items I deleted, and blindly press on with a glaring MIL. Hope you followed that logic.
Since I bought the engine\transmission combo already yanked out of the 2001 donor truck I don't have a complete EVAP sytem to show you, (you may have sourced yours the same way) so from what I investigated at the local junkyard, it appears it's a fuel line that runs from the fuel tank along the frame rail than hugs the transmission and up to the front of your intake manifold as a black plastic line, where it enters the intake via a valve which is regulated by the PCM.
Some folks when they do an engine swap get a three tube fuel sending unit, one for supply, one for return, and the third to vent into the atmosphere with a 2 foot rubber hose and a small check valve at the end. I don't have the check valve on mine yet and my truck in the garage does not emit stinkies, so I'm fine with that for now till I source the check valve (6 months later, hee hee).
Tunistas let's meet the nine EVAP codes:
P0440 Evaporative Emission System
P0442 Evaporative Emission System Leak Detected (small leak)
P0443 Evaporative Emission System Purge Control Valve Circuit
P0446 Evaporative Emission System Vent Control Circuit
P0449 Evaporative Emission System Vent Control Circuit Intermittent
P0452 Evaporative Emission System Pressure Sensor/Switch Low
P0453 Evaporative Emission System Pressure Sensor/Switch High
P1441 Evaporative Emission (EVAP) System Flow During Non-Purge
P1665 EVAP Vent Solenoid Control Circuit
Now let's look at the Black Magic that it takes to disable these codes, we have two controls:
If it was up to me I would break it up into a third control so it would look more like this:
- SES (Enable / Disable)
- MIL (MIL On First Error, MIL on Second Error, No MIL Light)
- Report Code (On / Off)
1. Again we start in the comfort of our own home, we fire up our laptop and launch the Editor. Open the file we saved in Step 3 of Section A. (Our last saved file is always our starting point).
2. Make changes in the Editor, this time we will make changes only to the Evaporative Emission System codes. Refer to the cheat sheet below and Disable the SES on these and set the MIL to No Error Reported:
P0440
P0442
P0443
P0446
P0449
P0452
P0453
P1441
P1665 - was already disabled on mine
3. Save the changes you made to a new file and call it something like "05 - Disabled O2s & EVAP"
4. Now you get to move the operation to your truck, hook up your HP Tuner to the OBDII port and then your USB cable to your laptop, turn the key to the ON position, launch the Editor program, and simply write the new changes to the PCM.
Note: sometimes you have to write the entire tune file to the PCM, sometimes it is perfectly happy with only writing what's changed, more on this later.
More words with each pic: